DALLAS (Reuters) - They may not believe in God or gods but they know a thing or two about them.

Atheists and agnostics topped a survey of religious knowledge among Americans released on Tuesday by the Pew Forum on Religion and Public Life.

"On average, Americans correctly answer 16 of the 32 religious knowledge questions on the survey. Atheists and agnostics average 20.9 ... Jews and Mormons do about as well, averaging 20.5 and 20.3 correct answers," Pew said.

It found Protestants answered 16 correctly and Catholics on average 14.7.

On questions about the Bible and Christianity, Mormons and white evangelical Protestants scored the highest, while Jews, atheists and agnostics trumped the other faiths on their knowledge of Buddhism, Hinduism and Judaism.

"While previous surveys by the Pew Research Center have shown that America is among the most religious of the world's developed nations, this survey shows that large numbers of Americans are not well informed about the tenets, practices, history and leading figures of major faith traditions -- including their own," said Pew, which is based in Washington.

To see the "U.S. Religious Knowledge Survey" go to: here

Highlights of the survey include:

_ More than four-in-10 Catholics do not know that their church teaches that the bread and wine used in Communion actually become the body and blood of Christ.

- About half of Protestants cannot correctly identify Martin Luther as the person who sparked the Protestant Reformation.

- Less than half identified Buddhism as the Dalai Lama's religion, 51 percent knew that Joseph Smith was Mormon and 54 percent correctly said the Koran is the Islamic holy book. More than 80 percent knew that Mother Teresa was Catholic.

- Nine-in-10 Americans know U.S. Supreme Court rulings do not allow teachers to lead public school classes in prayer. But two-thirds incorrectly said Supreme Court rulings prevent them from using the Bible as an example of literature.